Hi Michael,
Off the top of my head, but have you looked into a laser scanner mounted
on some sort of aerial platform such as a cherry picker? Not sure
whether the platform would be stable enough.
Alternatively a low level UAV flight may provide a detailed enough DTM
through stereo imagery analysis.
Cheers,
Andy
On 18/09/2014 10:43, Michael.Dodd wrote:
Any suggestions as to the best way to survey and interpolate ridge and
furrow grassland that is not on a flat plane?
I have tried various methods without success.
The ridge and furrow area that I want to map is about 120mx120m, the
ridge and furrow pattern is distinct with about 0.5m or difference
between ridge ht and furrow base but the pattern has a slight curve
towards one end and the land is not flat. If you are not sure what
ridge and furrow looks like then there is an example at 51.9827,
-0.9135, the stripes are clearly visible on the google earth image.
Mapping can be done with cm level dgps but does this require many tens
of thousands of points to be recorded. Or can fewer points be recorded
and qgis interpolation somehow be told to interpolate along the ridge
and furrow then fill in the area between them with some sort of curve.
The actual curve is also problematic as the ridge top tends to be
flattened and not a smooth sine wave. I don't have good LIDAR of the
area but even that resolution may not be good enough.
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Andy Harfoot
GeoData Institute
University of Southampton
Southampton
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Fax: +44 (0)23 8059 2849
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